Because of the widely spaced apart hulls of a catamaran, the boat is rather difficult to maneuver manually on land. Various types of dollies and other apparatus has been proposed for this purpose. For example, in "Hobie Hot Line" magazine, published by Hot Line Publications, P.O. Box C-19509, Irvine, California 92713, Volume 5, Number 7, dated November-December 1976, carry advertisements of two types of such apparatus. On page 6, a pair of spheres are mounted on an axle having opposite outer ends which receive adjacent ones of the hulls, with the spheres between the hulls. On page 11, dollies, one for each of the catamaran hulls, are advertised; each dolly having a pair of wheels positioned on opposite sides of the associated hull when it is positioned in the dolly cradle which receives only the keel portion of the hull, so that the hull may bounce out of the cradle. Also, the two wheels of each dolly would make it somewhat heavy, and likely to roll in a truck or station wagon.
A pair of dollies for a catamaran are shown in FIG. 11 of U.S. Pat. No. 3,436,774, and are but briefly described in column 5, line 16 of this patent. The drawing shows each dolly having a pair of wheels, one on each of opposite sides of the associated hull, with the cradle embracing only the lower quarter of the hull.
A single wheel dolly for the bow of a canoe is shown in U.S. Pat. No. 1,109,520. U.S. Pat. No. 3,687,476, shows a one wheel dolly having a cradle which receives only the keel portion of a single hull boat.
A pair of single wheel dollies, one for each of opposite sides of a single hull boat are shown in U.S. Pat. No. 3,271,798, but each dolly engages but one side of the hull. Other dollies of a somewhat similar nature are shown in U.S. Pat. Nos. 2,578,376 and 2,637,567.